import {
    INCREMENTCOUNT
    ,DECREMENTCOUNT
} from '../constant/countCount'

//定义reducer的初始值
const init ={
    count:0
}

export default function countReducer(prevStata=init,action){
    const {
        type,
        data
    }=action
    switch(type){
        case INCREMENTCOUNT:
            return{
                ...init,count:prevStata.count + data
            };
        case DECREMENTCOUNT:
            return {
                ...init, count: prevStata.count - data
            };

    }

    return prevStata
}